testing srst in h323 GW

[iptuser55]

I have a H323 GW configured with SRST. If it was MGCP , I would just shut down CCM Service so to force the phones and router in SRST and use the however how do you does this with a H323GW- I can not think at the moment so excuse the stupid question. I pointed two phones to a CCM service on sub3 and shut  down- the service  the phones went into SRST at the H323 GW - all good. However if the dial-peers of the H323 GW have multiple preferences set i.e DP 1 Points to SUB1, DP 2 points to SUB2 etc would I need to shut CCM Service on both SUB1 abd SUB2 for the GW to work i.e Incoming DDI to the phone?. I'm SRST with a H323 GW, how does the router know to send the call to the registered phone as opposed to the session target- is the fact it has registered to it or does it try the session target time out and the sends to call to the phone

thanks

[Clifford McGlamry]

Your dial peers will always follow the longest match rule.  Your system will have specific dial peers created dynamically when the phones register up in SRST.  So if your phone is extension 2001, you might have a dial peer to CCM that has the pattern 2...

However, the SRST dial peer created dynamically when the phone reigsters would be 2001$, which would be an exact match.

Since the longest match wins, it would go to the phone rather than a voip dial peer. 

Please rate helpful posts.

Cliff

[iptuser55]

Hi Cliff

thanks for the reply

In my H323GW the coming DDI are 7 digits long say 5551234, the DN`s have site codes say 222 so the registered DN is 2221234. When the CUCM is working, the call goes to CUCM and is translated in a translation Pattern - at some stage in the future we will convert the same GW to MGCP hence the Translations in CUCM.

I`ve set up mirror translation in the GW under call-manager-fallback rule 1 /^555/ /222/  so if I shut down the CCM service which the Dial-peer uses then SRST should time out and use Dial-peer of the registered phone?

As I have multiple preferences on the dial-peers for redundancy pointing to the SUB`s should I shut all all CCM Services each of the dial-peers are pointing to ?

[Clifford McGlamry · Accepted solution]

Since the incoming T1 is under control of H323 and not MGCP, it will never fail over to call-manager-fallback control.  That method isn't going to work for you.

What you need to do is create a voice translation-rule and pattern to do the digit manipulation on your incoming calls at the voice-port when the call arrives.  Then you can modify the dial peer to support the 3 digit site code + the number.  As long as the phones register with the same number, you'll be okay.

If your phones register without the 3 digit site code, then you'll need to perform those digit manipulations on the call on the other end of the voip connection (i.e. using a translation pattern in the CSS of the gateway on CCM, or by simply prefixing the incoming calls in the gateway config itself.

Cliff

[iptuser55]

cliff

thanks, thats what I thought I had to do